Hepatocellular adenoma (inflammatory type)

Case contributed by Dr Jan Frank Gerstenmaier

Presentation

A liver lesion was incidentally detected on CT IVP done for haematuria. For further investigation.

Patient Data

Age: 41
Gender: Female

Arterially hyperenhancing liver mass segment 7

MRI

MRI liver with Primovist

The liver is of normal volume. There is no evidence of liver cirrhosis or hepatic steatosis.

Lesion 1: Segment 7,

23 mm x 31 mm x 27 mm, T2 hyperintense, slightly hyperintense on T1 in phase, signal drop on T1 opposed phase indicative of intralesional fat. Avid arterial enhancement with washout. No hepatocyte specific contrast agent uptake.

Lesion 2: Segment 6, 5 mm, not seen on T2-weighted imaging, DWI, or lipid sensitive imaging. No enhancement. Lack of hepatocyte specific contrast agent uptake.

Lesion 3: Segment 7, 8 mm, not seen on T2-weighted imaging, DWI, equivocal lipid content. No enhancement. Lack of hepatocyte specific contrast agent uptake.

Within segment 3, there is a 12 mm somewhat wedge shaped area of hypoenhancement identified, not seen on any other sequences. Not visible on CT

Within segment 7, there is a ovoid area of concentrated contrast agent and delayed and hepatocyte specific phase, likely representing a focally dilated bile duct.

The hepatic arterial anatomy is conventional. The portal vein and hepatic veins are patent. The biliary tree is of normal calibre. The gallbladder contains sludge. There is no evidence of gallstones.

The pancreas is normal in appearance. The main pancreatic duct is not dilated.

The kidneys, spleen and adrenal glands are normal in appearance.

There is no free fluid or lymphadenopathy.

Conclusion:

There are no imaging features to suggest cirrhosis. Despite this, the liver mass in segment 7 is suspicious for a well-differentiated HCC, particularly given the heterogeneous contrast enhancement, lesion capsule, high T2 signal and rapid washout. The lipid content and other imaging features overlap with hepatic adenoma. The subcentimetre lesions in segments 3, 4a, 6 and 7 are indeterminate but may well represent further adenomas. Does this patient have risk factors for hepatoma? Is this patient on the oral contraceptive pill?

 

Pathology

Resection of liver mass.

Unpaired artery in left upper quadrant indicated that this is not normal liver. Fat content shown mainly in lower half of image.

MACROSCOPIC DESCRIPTION: 1. "Segment 7 liver resection": A liver segmentectomy 110 x 80 x 35 mm and 196 g. There is a resection margin 105  x 80 mm (inked black). Adjacent to the resection margin there is an area where the capsule has been stripped 75 x 45 mm (inked blue). The remaining liver capsule is shiny smooth and unremarkable. There is a well demarcated rubbery tan tumour 31 x 25 x 19 mm. The tumour is 14 mm from the resection margin and 3 mm from the unremarkable liver capsule. The remaining liver is unremarkable. BLOCK DESIGNATION: A - tumour with resection margin. B-C - tumour with liver capsule. D-E - tumour with adjacent normal liver parenchyma. F - normal liver. P6. 2. "4A liver resection": An irregular piece of liver 32 x 17 x 15 mm, 3.8 g. The surface inked all black. Sectioning reveals unremarkable liver. A focal lesion is not identified. 6xTS. A3. (SK)

MICROSCOPIC DESCRIPTION: 1. Sections of the liver show a well demarcated tumour comprising cords of bland hepatocytes 1-2 cells thick, separated by sinusoids. The architecture is haphazard and lacks normal portal tracts. The tumour cells have abundant granular eosinophilic cytoplasm with occasional steatosis, round nuclei, speckled chromatin and conspicuous nucleoli. Mitosis and necrosis are not seen. There is no lymphovascular or perineural invasion. The tumour is 10mm from the resection margin and 5mm from the liver capsule. Liver parenchyma adjacent to and away from tumour shows intact normal lobular architecture. There is a mild, patchy portal infiltrate of lymphocytes and occasional eosinophils. A mild sinusoidal infiltrate of neutrophils is present, which occasionally is more prominent at central venules. There is no evidence of cirrhosis. Reticulin stains to follow. 2. Sections show liver parenchyma with intact normal lobular architecture. There is a mild portal infiltrate of lymphocytes, plasma cells and occasional eosinophils, however there is no expansion of portal tracts or infiltration of biliary epithelium. The lobules show a mild patchy sinusoidal infiltrate of neutrophils. A focal lesion is not identified.

DIAGNOSIS: 1. Segment 7 liver: Hepatocellular adenoma, completely excised. 2. Segment 4A liver: Liver parenchyma with mild non-specific portal infiltrate. No focal lesion identified. SUPPLEMENTARY REPORT Further levels on specimen 2 show a benign haemangioma. Final diagnosis 2. Segment 4A : Benign haemangioma.

SUPPLEMENTARY REPORT: (18/9/14) The tumour cells are CRP positive. There is no loss of staining with L-FABP. Glutamine synthetase is negative. This immunoprofile is in keeping with inflammatory hepatocellular adenoma.

Case Discussion

This is an inflammatory-type hepatocellular adenoma, one of four recognised types (40–55% of cases), the other three being HNF1A-mutated HCA (30–45%); CTNNB1-mutated HCA (10–15%); unclassified (10%).

PlayAdd to Share

Case information

rID: 30999
Case created: 15th Sep 2014
Last edited: 7th Nov 2017
Inclusion in quiz mode: Included

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.